Remote operating tool for electrical apparatus

ABSTRACT

AN ELECTRFICALLY INSULATED GRIPPING TOOL HAS A PAIR OF OPPOSED, CONCAVO-CONVEX JAWS JOINED TO RESPECTIVE, HINGEDLY INTERCONNECTED, SPRING-LOADED ARMS. THE ARMS ARE COUPLED TO A MANUALLY RECIPROCABLE PLUNGER CARRIED WITHIN AN OPEN-ENDED TUBE, AND EXTENSION OR RETRACTION OF THE PLUNGER CAUSES OPPOSED OUTER CAM SURFACES ON THE ARMS TO ENGAGE THE TUBE AT ITS OPEN END AND EFFECT OPENING OR CLOSING OF THE JAWS RESPECTIVELY. THE LEADING ENDS OF THE JAWS ARE CONFIGURED TO PROVIDE CLEARANCE FOR THE TERMINAL LEG OF A CONNECTING ELBOW HELD BY THE TOOL, AND OPPOSED OPEN AREAS ON THE JAWS DEFINE RESPECTIVE SECTIONS OF AN APERTURE FOR CLEARING THE TRANSVERSE CABLE LEG OF THE ELBOW.

Sept. 21, 1971 J. P. DAVIS 3,606,660

REMOTE OPERATING TOOL FOR ELECTRICAL APPARATUS Filed NOV. 25, 1969 I N VEN TOR dofm P. Dar/5 ATTORNEY-5.

United States Patent U.S. Cl. 29-203 7 Claims ABSTRACT OF THE DISCLOSURE An electrically insulated gripping tool has a pair of opposed, concavo-convex jaws .joined to respective, hingedly interconnected, spring-loaded arms. The arms are coupled to a manually reciprocable plunger carried within an open-ended tube, and extension or retraction of the plunger causes opposed outer cam surfaces on the arms to engage the tube at its open end and effect opening or closing of the jaws respectively. The leading ends of the jaws are configured to provide clearance for the terminal leg of a connecting elbow held by the tool, and opposed open areas on the jaws define respective sections of an aperture for clearing the transverse cable leg of the elbow,

This invention relates to electrical maintenance equipment and, more particularly, to an insulated, manually operable tool for gripping and manipulating an electrical conductor connector, so as to permit connection and dis connection of such connector from a mating terminal while current is flowing through the line.

Insulated connectors are utilized in many situations, such as for connecting cables to transformers and other ap paratus. With the expansion of underground electrical service, particularly for residential distribution, transformers and connectors have been located inside of enclosures beneath the surface of the ground instead of above the sufrace as has heretofore been the case. For reasons of maintenance or repair it often becomes necessary to remove the connectors from the underground transformer to which it is attached, but frequently the enclosure has only limited clearance, thereby making the maintenance of the connectors somewhat difficult. Further, in order to provide uninterrupted service, it is usually desirable to service the transformer with current flowing through the line.

In view of the underground location of the enclosures, the space limitations associated therewith, and the danger of servicing such installations while current is flowing, it is desirable to have a suitable insulated device for pulling and maneuvering the transformer connectors which permits the lineman to position himself at a safe distance from the enclosure.

Accordingly, it is an important object of the present invention to provide an insulated, remote operating tool which allows a workman to remove, install, or otherwise manipulate a connector, fuse or the like on a hot line at a safe distance therefrom while affording secure, positive gripping of the connector without damaging the same.

Another important object of the present invention is to provide a gripping tool as aforesaid which perimts rotation of the entire tool as a unit without losing grip of the connector, thereby permitting the connector to be broken loose from its frictional connection with the mating terminal.

A further important object of the instant invention is to provide such a maintenance tool wherein opening and closing of the gripping jaws thereof is easily operated and controlled by straight-line manipulation of the actuating component of the tool.

In the drawing:

ice

FIG. 1 is a fragmentary, elevational view of an operating tool embodying the principles of the present invention shown in use with a connector elbow, parts of the tool being shown in section for clarity;

FIG. 2 is a fragmentary, top plan view thereof;

FIG. 3 is an enlarged, plan view of the open jaws of the tool shown in FIGS. 1 and 2, one jaw being shown in cross section to reveal details of construction;

FIG. 4 is an end elevational view thereof; and

FIG. 5 is a fragmentary, cross-sectional view taken along line 55 of FIG. 1, the outline of the connector elbow being indicated by dashed lines.

The operating tool 10 illustrated in the drawing is especially well suited for use with connectors having an elbow configuration, and basically comprises a jaw assembly 12 and an actuating assembly 14 operably connected thereto. The jaw assembly 12 includes a pair of opposed jaw members 16 and 18 rigid to one end respectively of a pair of elongated, hingedly interconnected arms 20- and 22. The ends of arms 20 and 22 opposite jaw members 16 and 18 respectively have lugs 24 which are pinned to the outstanding ears 26 of a rigid eye member 28.

Opposing stub posts 30 on the interior surfaces of arms 20 and 22 carry a return spring 32 therebetween which biases the members 16 and 18 into their normal, spaced apart disposition shown in FIGS. 3 and 4. Extensions on the arms 20 and 22 beyond the lugs 24 carry adjustable, elongated stops 34- which extend transversely through each arm 20 and 22 to engage the proximal outer surfaces of eye 28 whereby to limit the opening of members 16 and 18.

The members 16 and 18 may be integrally molded with the corresponding arms 20 and 22 as shown in the drawing, or they may be constructed as independent units and joined together by suitable means not illustrated. In either event the members 16 and 18 may preferably be constructed of a suitable glass fiber material for insulation purposes, or of a suitable metallic material which has been clipped in an insulative plastic or rubberized coating Members 16 and 18 are generally concavo-convex in configuration and present opposed, generally concave inner surfaces 36 for complementally receiving the outer surfaces of the connector elbow 38 which is used for connection to the terminal 40 shown in FIGS. 1 and 2. The elbow 38 presents a female terminal leg 42 adapted to frictionally receive the mating terminal 40', and an intersecting cable leg 44 transverse to leg 42 adapted for joining to a cable.

As may be seen most clearly viewing FIGS. 3 and 4, the rear of each member 16 and 18 is closed, while the leading marginal portions 46 thereof continue the concavo-convex configuration of the bodies of the members and are open. In this manner the opposed portions 46 define an opening therebetween when members 16 and 18 are closed whereby to permit clearance of elbow leg 42 when the latter is held by the tool 10. Similarly, the marginal sections of members 16 and 18 disposed rearwardly of portions 46 are configured to present opposed, generally semi-circular open areas 48. Areas 48 are aligned to define an aperture transverse to the opening formed by portions 46 when members 16 and 18 are closed for clearing elbow leg 44.

The actuating assembly includes an elongated, tubular preferably glass fiber element 50 open at one end thereof, and insulated plunger unit 52 shiftable within element 50 for movement toward and away from the open end. The plunger unit 52 has a releasable catch 54 extending from one end thereof which may be used for coupling the jaw assembly 12 thereto by means of the eye 28. The leading edge 56 of element 50 at the open end thereof is configured to present a pair of opposed guide notches 58 therein which are adapted to receive the arms 20 and 22 3 of jaw assembly 12 for prohibiting rotation of assembly 12 relative to element 50 during operation. Opposed, mutually cooperable cam surfaces 60 are provided on the outer stretches of arms 20 and 22, and are engageable with corresponding rear sections of edge 56 within the notches 58.

It may be seen that operation of the tool is accomplished by manual straight-line reciprocation of the plunger unit 52. Initially, the jaw members 16 and 18 may be opened as in FIG. 3 by extending unit 52 to the extent that the jaw arms 20 and 22 are disposed outside of the open end of element 50. In the instance where the elbow 38 is to be removed from terminal 40, the element 50 may be used to position the members 16 and 18 about elbow 38, being careful to properly align the same to bring the opposed open areas 48 in alignment with cable leg 44. Subsequent retraction of the plunger unit 52 relative to element 50 causes movement of the jaw assembly 12 therewith to bring arms 20 and 22 within the notches 58.

Further relative movement of unit 52 causes cam surfaces 60 to bear against the portion of edge 56 in notches 58 and swing members 16 and 18 together against the force of spring 32 to close about elbow 38. Unit 52 may be retracted until a firm, positive grip is maintained on elbow 38 and may be secured in such a disposition by suitable latch means (not shown). It may be seen that in the position as shown clearly in FIGS. 1 and 2, the elbow 38 is securely held by members 16 and 18 and that, if necessary, tool 10 may be twisted in order to break loose the frictional connection between elbow 38 and terminal 40.

Replacement of an elbow 38 into engagement with terminal 40 is a simple reversal of the above process, wherein extension of unit 52 relative to element 50 causes the arms 20 and 22 to move outside of element 50 such that spring 32 returns members 16 and 18 to their normal, spaced apart conditions of FIG. 3. It may be appreciated from the above showing that the present invention provides a tool which is simple yet safe to operate, and which is particularly advantageous in those situations which require remote manipulation of the electrical connection members. Further, the basic straight-line actuation feature of the invention provides control and ease of handling which has heretofore not been available.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. A tool for positively gripping and manipulating an electrical connecting elbow presenting intersecting cable and terminal legs, said tool comprising:

an elongated tubular element open at one end thereof;

a plunger unit shiftable within said element for movement away from said open end;

a jaw assembly coupled to said plunger unit for movement therewith and provided with a pair of normally spaced-apart, opposed, relatively shiftable jaw members extending outwardly from said open end of the element and having inner surfaces configured to grip and hold the corresponding outer surfaces of said elbow;

guide means on said element adjacent said open end thereof; and

cam structure carried by said jaw members, shiftable past said open end of the element, and engageable with said guide means during retraction of the plunger unit for causing the members to be shifted together for closing about said elbow,

said members having opposed, leading marginal portions configured to define an opening therebetween when the members are closed about the elbow for clearing said terminal leg thereof, and having opposed marginal sections configured to define an aperture therebetween transverse to said opening when the members are closed for clearing said cable leg of the elbow.

2. A tool as set forth in claim 1, wherein is provided a pair of elongated arms rigidly joined at one end to said jaw members respectively and pivotally coupled at the other end to said plunger unit, said arms having outer surface stretches engageable with said guide means, said cam structure including said outer stretches.

3. A tool as set forth in claim 2, wherein is provided a pair of opposed notches in said tubular element at said open end thereof for receiving said arms respectively upon retraction of said plunger unit whereby to prohibit rotation of said jaw members relative to said element.

4. A tool as set forth in claim 3, wherein said open end of the element presents a leading edge configured to define said notches, said outer cam stretches of said arms being engageable with said leading edge, said guide means including said leading edge.

5. A tool as set forth in claim 1, wherein is provided spring means between said members yieldably biasing the latter apart.

6. A tool for facilitating connection and disconnection of one conductor connector from a mating connector, said tool comprising:

an elongated tubular element open at one end thereof;

a plunger unit within the element and mounted for shifting movement therein toward and away from said open end; and

a jaw assembly coupled to said plunger unit for movement thereby and provided with a pair of relatively movable jaw members configured to grip and hold said one connector when moved toward one another into gripping disposition and to release the connector when shifted apart,

said jaw members having opposed, mutually cooperable cam surfaces thereon engageable with said element at said open end thereof for causing the members to be shifted toward each other into said connector gripping disposition as the jaw assembly is moved into at least partial telescoped relationship within the tubular element upon movement of the plunger unit away from said open end of the element.

7. A jaw assembly for gripping an electrical connecting elbow presenting intersecting cable and terminal legs, said assembly comprising:

a pair of normally spaced apart, opposed, relatively shiftable jaw members having inner surfaces configured to grip and hold the corresponding outer surfaces of said elbow,

said members also having opposed, leading marginal portions configured to define an opening therebetween when the members are closed about the elbow for clearing said terminal leg thereof, and having opposed, marginal sections configured to define an aperture therebetween transverse to said opening when the members are closed for clearing said cable leg of the elbow.

References Cited UNITED STATES PATENTS 3,136,040 6/1964 Bauer et al. 29-203H THOMAS H. EAGER, Primary Examiner US. Cl. X.R. 29-203H 

